Need help, Spitfire mkIV the speed was playing up, reading below the speed and distance it should, the engine has been changed to a 1500, but still has the original gearbox (I think). I’ve had the car resprayed, but somehow they seem to have blown all the gauges and radio. I had brought some second hand gauges so replaced them easily. The originals were jaegar which I’m planning to get refurbished, the speedo is now seized. So the new gauges are smiths, when I connect the speedo I get no reading at all, I checked everything was ok at the speedo end, which it was, I managed to get the gearbox end off ok but the thread is stripped on the gearbox so I don’t think it was engaging properly. Is this easy to change on the car with the gear box tunnel removed? And is it ok to drive the car with nothing plugged into the gearbox? (I have a gps speedo). Thanks